Electronic Alarms and Home Security Devices - How are doors wired?

I bought a home with a system already installed. No manual, No codes, only the physical equipment. After hunting around I was able to figure out that it's a First Alert FA148C. So I tracked down manuals for that system (and a Ademco Vista 10p since I understand that they are very similar if not identical).

I've input new codes and the system works (i.e. arming, disarming, bypassing zones). I do have 1 zone (specifically zone 06) that refuses to go into "ready". So I can arm the system but only when I bypass zone 06. A few slips of paper in the PC box (and a placard I found later) indicate that zone 06 is the basement door.

I am pretty sure the floor near the door was replaced. I think the floor installers "mucked up" the door sensor. So all signs point to the basement door being zone 06.

How are these wired? In looking at the joist under the door, I can see alarm wires running to the general area of the door, but I'm not sure how these are typically wired. Where around the door should I be looking for contacts (i.e. hinge side by the floor, latch side by the floor, at the latch, etc)? Anyone have any diagrams of typical installs? I've looked at the front and back doors, but it's still not obvious to me how these are wired. Any ideas are welcome.

Thanks
John

Look for a circular outline about 3/8" across (it may be under a layer or two of paint). That's the contact; and it can be pretty much anywhere on the doorframe (usually on the header or latch side. If you don't see one, they may have replaced the door frame without replacing the contact. If the contact is in the door frame, stick a magnet against it. If your zone closes, then the door itself may be missing the matching magnet (or it's simply misaligned).

Mr Ron Thanks for the Quick Reply!

I found the contact point about 6 inches up from the floor on the latch side (and another on the door itself). While I only had a few minutes last night to investigate, I did try the magnet trick and unfortunately No Joy.

So my thinking right now is that the wires are pinched or cut. I'll continue investgating from the basement.

Is it worth trying to dig out the contact on the latch side of the door frame and re-fishing? The indentation/recess on the door frame was about an 1 inch, so my guess is that the contact is larger than 3/8". Are these type of contacts stock items at home improvement stores?

Thanks Again,
John

There are a couple of versions that are 3/4". Sadly, they aren't hardware store items, and even Radio Shack has stopped reliable stocking them. There are a bunch of reliable online vendors of alarm parts, just judge them like any other online purchase.

The next step of zone troubleshooting is to pry the contact out, and short the wires on the back together. If the zone closes, then you have a bad contact, if not, then the problem is the wiring between the door contact and the head end.

Prior to your email, I did have some time to dig out the contact from it's entombment in caulk. I was able to confirm 2 things; (1) the wire was cut, and (2) shorting the "live" side cleared the zone 06.

My next step is to reconnect the contact head and use your magnet test to confirm the head is good. Assuming it checks out, it should be a straight forward fish/re-wiring job.

Thanks You Very Much For Your Assistance!!!
John

Maybe you could answer another question. It seems like all the entry points (doors, windows, etc) each wire goes through little white wiring device labeled Dolphin. It kind of looks like heat shrink tubing. Except typically with heat shrink the connection is inline, while with these the wires go in and out the same side. I assumed these were resistors to identify the specific zone/entry point. Is that correct? or even close?

They're B connectors.
http://www.amazon.com/Dolphin-DC-100S-Super-Connector-Sealant/dp/B000JP3GB6

(Mods, if it's not allowed to link to something on another site please forgive me and delete this)

Thanks OldGrouchy!

I finished the fix over the weekend. Re-fished the wire and re-connected, everything works as originally designed.

I appreciate the help!
John